body:before {
    background: url(
    https://xwt-leyou.oss-cn-shanghai.aliyuncs.com/timg.jpg) center/cover no-repeat;
    content: '';
    background-repeat: no-repeat;
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    z-index: -1;
    opacity: 0.8;
    -webkit-filter: grayscale(40%);
    -moz-filter: grayscale(40%);
    /*-ms-filter: gray(40%);*/
    -o-filter: grayscale(40%);
    filter: grayscale(40%);
}

.box{
    background: url(https://xwt-leyou.oss-cn-shanghai.aliyuncs.com/2.jpg) center/cover no-repeat;
    width:500px;
    margin: 0 auto;
    background-color: bisque;
    height: 700px;
    margin-top: 20px;
}

.sui-form{
    text-align: center;
}

.input-xfat{
    margin-top: 10px;
    border-radius: 4px;
    width: 200px;
    height: 25px;
}
.setting{
    margin-top: 10px;
}
.buttonm{
    margin-top: 10px;
}
.forget{
    color: #0000ff;
}
.register{
    float: right;
    margin-right: 10px;
}
/*filter: gray;*/